^There are 12 lines operated by NJ Transit, including the MTA Metro-North Railroad Port Jervis Line which in this list is counted with the MTA Metro-North Railroad entry in the table.

^The Peninsula Commute service has been running since 1863 over largely the same route. The State of California took over financial responsibility from Southern Pacific in 1980 and renamed the service to Caltrain.

^ abThis is the Average Daily Ridership figure, not an "Average Weekday Ridership" figure – it is averaged from the 2017 Total Ridership figure for this system.